21012212221000 has 1024 divisors, whose sum is σ = 68588709396480. Its totient is φ = 5814144000000.

The previous prime is 21012212220953. The next prime is 21012212221031. The reversal of 21012212221000 is 12221221012.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 2913907395 + ... + 2913914605.

It is an arithmetic number, because the mean of its divisors is an integer number (66981161520).

Almost surely, 2^{21012212221000} is an apocalyptic number.

21012212221000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21012212221000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34294354698240).

21012212221000 is an abundant number, since it is smaller than the sum of its proper divisors (47576497175480).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21012212221000 is a wasteful number, since it uses less digits than its factorization.

21012212221000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7375 (or 7361 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21012212221000 its reverse (12221221012), we get a palindrome (21024433442012).

It can be divided in two parts, 21012212 and 221000, that added together give a palindrome (21233212).

The spelling of 21012212221000 in words is "twenty-one trillion, twelve billion, two hundred twelve million, two hundred twenty-one thousand".